Dumping mine waste into Lakes - Is this the best environmental option?

Vancouver, Canada - Sixteen Canadian lakes are slated to be officially but quietly "reclassified" as toxic dump sites for mines. Under the Fisheries Act, it’s illegal to put harmful substances into fish-bearing waters. But, under a little-known subsection known as Schedule Two of the mining effluent regulations, federal bureaucrats can redefine lakes as "tailings impoundment areas."  Public opposition has been fierce, but experts say using lakes is the least environmentally destructive method of storing mine tailings.

Since 2002, Schedule Two has allowed mining companies to dump mine waste into freshwater bodies.  Last fall, Federal Court Justice Luc Martineau ruled that federal bureaucrats acted illegally in trying to fast-track the Red Chris copper and gold mine without a full and public environmental review.

The decision put the project on hold, but in early June 2008, the Federal Appeals Court reversed the decision, paving the way for federal officials to declare lakes to be dumps without public consultation.

Environmentalists say the process amounts to a "hidden subsidy" to mining companies, allowing them to get around laws against the destruction of fish habitat.

"This is a precedent-setting decision by the federal government to start using fish-bearing habitat as a waste management area," said Jim Bourquin of the Cassiar Watch Society, a BC conservation group.

Catherine Coumans, spokeswoman for the environmental group Mining Watch, said the federal government is making it too easy. She said federal officials are increasingly using the obscure Schedule Two regulations to quietly reclassify lakes and other waters as tailings dumps.

"Something that used to be a lake - or a river, in fact, they can use rivers - by being put on this section two of this regulation is no longer a river or a lake," she said. "It’s a tailings impoundment area. It’s a waste disposal site. It’s an industrial waste dump." Coumans said the procedure amounts to a subsidy to the industry and enables mines to get around the Fisheries Act.

In northern B.C., Imperial Metals plans to enclose a remote watershed valley to hold tailings from a gold and copper mine. The valley lies in what the native Tahltan people call the "Sacred Headwaters" of three major salmon rivers. It also serves as spawning grounds for the rainbow trout of Kluela Lake, which is downstream from the dump site.

The dump site includes two small lakes in a Y-shaped valley. Imperial Metals plans to build three dams to contain mine tailings within the valley. Environmentalists say there is no way to stop effluent leaking downstream in groundwater.

But Steve Robertson, exploration manager for Imperial Metals, told CBC News the dump site will be sealed and that the economic benefits of the planned Red Chris mine will be enormous.  "This is a project that can bring a lot of good jobs, long-term jobs, well-paying jobs to a community that desperately needs it," Robertson said.

He added that the total investment over the 25-year life of the mine would be about half a billion dollars and that the risk to the environment will be carefully managed.

"Tailings are part of the mining process," Robertson said, "and, if treated properly, if they’re built into a proper structure and kept submerged, they should be able to withstand the test of time and actually not pose a detriment to the environment."

Similarly, Brazilian mining giant Vale Inco Ltd. is planning to dispose of mine tailings from its proposed nickel processing plant in Sandy Pond Lake, Newfound Land.  Vale Inco contends that using Sandy Pond to contain the residue, which will include acid-generating sulphur, will cause the least harm to the environment.

"We take these issues quite seriously. We’ve done an exhaustive analysis of the alternatives that would be available to us for the residue management. We’ve looked at alternative sites including an excavated structure and on balance, our analysis shows, our best alternative is to use Sandy Pond. It’s something that we looked at very, very carefully," Vale Inco spokesman Bob Carter said in an interview.

The federal Department of Fisheries and Oceans agrees. DFO officials have concluded that using Sandy Pond is the best option for the project. They have referred the request to Environment Canada which is heading a process that could see Sandy Pond added to the list of approved tailings impoundment areas.

Environment Canada’s chief of mining and minerals, Chris Doiron, conceded that using lakes for tailings disposal can be an emotional issue for many Canadians. Yet in a few select cases, he says, it the best option.

"As a bottom line it is sometimes what makes the most environmental, technical and socio-economic sense. But it must always be subjected to a very exhaustive environmental assessment process," he said in a Globe and Mail article.

Last year Environment Minister John Baird called for tough reporting standards for such mine wastes and has directed his officials to determine how best to make such information public. This call for action followed in the wake of a formal suit filed against him in the Federal Court by two environmental groups for not divulging information about mine tailings, long considered a most hazardous aspect the mining process. See article: Mining industry responds to cover up allegations.

Submerging tailings and mine waste under water is widely considered the best way to prevent oxidization of the material which could release toxic substances into the environment. Most mineral bodies in Canada are sulphides which can create acid-producing waste. Storing tailings or residue on land can lead to acid drainage.

Vale Inco estimates the total construction and operating costs of using Sandy Pond to contain the residue will be $62-million while the cost of constructing and operating a human-made excavated pit for storage would be $490-million.

Lakes are often the best way for mine tailings to be contained, said Elizabeth Gardiner, vice-president for technical affairs for the Mining Association of Canada (MAC).

"In some cases, particularly in Canada, with this kind of topography and this number of natural lakes and depressions and ponds … in the end it’s really the safest option for human health and for the environment," she said.

A statement on the Association’s website notes that through decades of research undertaken by governments and the mining industry, we are gaining an ever-increasing understanding of the complexities involved in the proper and safe storage of mine tailings and waste rock. "This work continues to support the fact that water covers provide an effective means of managing mine waste and tailings."

Toxic mine tailings can be stored either in water or on land, Minister of Fisheries and Oceans Loyola Hearn said in the House of Commons, after the Canadian government was accused of putting fish and fish habitat at risk.

"It is much more responsible to store them in water," Hearn said. "Any water that is damaged in any way, there has to be assurance that there is no net loss to either fish or fish habitat. Mitigation has to occur, it always occurs, and when it doesn’t occur, the company does not get a permit to move ahead with the operation."

According to Marilyn Scales Field Editor of the Canadian Mining Journal, the Island Copper mine on Vancouver Island deposited tailings underwater for 25 years. Since the mine closed in December 1995, follow-up environmental reports found that widespread heavy metal contamination was avoided. On the whole, the submarine scheme resulted in less severe impacts that a land-based impoundment area would have.

Ideally, mining companies would build containment ponds for their toxic waste, said Hearn. However, the rugged terrain surrounding many mining operations doesn’t always allow such structures to be built.


There is little doubt that mining is integral to Canada’s economy. Canada’s mining industry (mining, mineral processing and metal producing industries) contributed over US$40 billion of Canada’s GDP in 2006.  Canada has over 2360 associated firms supporting domestic and global mining activities and over 65% of the world’s mining companies are listed in Canada. Almost 80% of Canada’s mineral and metal production is exported, making it one of the world’s largest exporters.

A June 2008 study published by Five Winds/Strandberg Consulting also found that the Mining Association of Canada’s (MAC) Towards Sustainable Mining (TSM) initiative has positioned Canada’s mining industry as a leader in sustainable development.

Part of the problem may be communication.  By trying to fast-track approvals and bypass the public consultation phase, the general public feels deceived.

According to Justice Martineau the decision by federal officials to skip a public review regarding the Red Chris copper and gold mine, had "all the characteristics of a capricious and arbitrary decision which was taken for an improper purpose."  He also found those officials "committed a reviewable error by deciding to forgo the public consultation process which the project was statutorily mandated to undergo."

Above and beyond the communications issue, however, the fundamental issue remains that using lakes or any body of water as a dumping ground for mine wastes will undoubtedly affect the natural eco-systems and will have environmental consequences. And environmental consequences will inevitably lead to social unrest and confrontation, a situation the industry would very much like to avoid.

If lake storage truly is the best ‘trade off’ option, mining companies may do well by including the public for the sake of education and awareness.  Trade offs imply winners and losers, and the mining sector will have to accommodate both sides of the equation. Transparency and public inclusion builds trust; working in secret achieves the opposite.

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